It's time to look at replacing my extractors on the 1275. I currently have rubbish Perry-style 3-1 extractors that are starting to leak out the centre pipe.

Engine is a worked 1360, 286 cam, ported head, dell'orto. But I'm trying to tune it for good mid range rather than top end, so have leaned to the smaller size on carburettor chokes etc. So far so good, the engine goes hard

So in keeping with this, I was considering fitting the Maniflow freeflow extractors instead of the more common LCB. I've always found LCBs a PITA anyway....

Just like to know if anybody is running this setup on a worked 1275, and whether you'd recommend it!

Bear in mind anything I fit will be an improvement over what I've currently got

yes we have fitted plenty of these, but i`m affraid to say that i havn`t done any specific "back-to-back" dyno testing to see conclusively any differences between the 2 types

but i am a fan of them for mildly worked 1275-1360s for road use, no problems at all

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

Ultimate hp isn't that important - this is a budget performance engine, using a combination of components based on what trick bits I had lying around!

Sounds like I'll give them a go. Is it likely to be a problem that the 1275 is higher than the small bore motors?

no i havn`t found any dramas fitting them, the height (so far) hasn`t been a problem & we`ve fitted quite a few (maybe 5 sets so far)

& i`m a fan of them """Because""" they seem to help the lower & mid-range power spread,,, so yeah i`m a fan of them for road cars

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

Thanks Matt, that's exactly what I want to hear!

I've fitted a heap of them too. Usually go straight on, but the last set needed so heat, wasn't set right. Work well, that's true but in all fairness, I seriously doubt you'd even be able to measure any HP benifit from these over most others on the market.

One thing I don't like about them is they can be a bugger to get apart, but that's true of most exhausts. The Perry with slip joint I do like for that reason, but you have to be sure your engine steadys and mounts are always in tip top condition.

Just also make sure that the flange thickness closely matches that of your inlet manifold too.

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Maniflow freeflows tend to crack at the top Y connection, more so on rodchange boxes due their poorer location.
I've seen a few do this. Make sure both your steady bars and rubbers are in good condition.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

If I end up having to get the exhaust welded/modified to fit the extractors, should I look at fitting a flex pipe?

I fitted maniflow LCB to my last mini the freeflow are probably for a smaller capacity engine , I had trouble with my maniflows as the flanges that attach to the head were not flat check them before you fit them .

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That's why it's good to be.............ME

Same here, I had to grind the centre flange flat on both my Maniflows. They burn gaskets if you don't.
Hate to say it, but the Chinese Maniflow copies seem better made..

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.